Modern ostomy appliances are commonly attached to the body by means of an adhesive wafer. The adhesive wafers most commonly used are designed to have a predetermined, fixed shape. The wearer cuts the central opening of the adhesive wafer to match his or her stoma size and shape, using scissors to cut along guidance lines that are pre-printed on the adhesive release sheet for certain standard sizes.
In a so-called one-piece appliance, the adhesive wafer is permanently attached to the appliance, to the extent that the adhesive wafer cannot easily be separated without risk of damaging the appliance. A one-piece appliance is intended to be used as an integral unit. A complaint sometimes made about one-piece appliances is that it is not always easy for elderly, visually impaired, or non-dexterous persons to adapt the size of the central opening in the adhesive wafer, because the appliance obstructs access from one side.
In a so-called two-piece appliance, the adhesive wafer forms part of a separate body fitment component that is attached by a releasable coupling. A two-piece appliance permits the body fitment to be separated from the appliance without damage, so that at least one of the components continues to be functionally usable. For example, the body fitment may remain in place on the body, and a replacement pouch mounted in place of a used pouch. While a two-piece appliance allows better access for adapting the wafer, a common complaint about two-piece appliances is that it is not always easy to align the components, particularly for elderly, visually impaired or non-dexterous users.
U.S. Pat. No. 6,840,924 describes an improved one-piece or two-piece ostomy appliance including a moldable adhesive, in which at least a portion of the adhesive can be manually molded by the wearer, to provide a custom fit around the stoma. This alternative way of customizing the wafer offers the prospect of a better fit around the stoma than that obtainable by cutting along standard size guidelines. Achieving a good fit is desirable in order to reduce the exposure of the peristomal skin to stool exiting the stoma. Peristomal skin may be quite sensitive, and vulnerable to irritation or infection when contacted by stool. Stool exiting the stoma may contain digestive juices from the body, and such juices can also attack the peristomal skin resulting in excoriation. Contact by stool also progressively reduces the effectiveness of the adhesive. However, stomas have many different sizes and shapes. The advantage of a moldable adhesive as taught in U.S. Pat. No. 6,840,924 is that the user can mold the adhesive to closely match the exact size and shape of the stoma.
In a form in which the appliance of U.S. Pat. No. 6,840,924 is implemented as a two-piece ostomy appliance, the wearer is able to access the moldable adhesive from both sides, including the non-body-contacting side, when the pouch is separated from the body fitment. This can enable the wearer easily to mold the adhesive, e.g., by folding or rolling it back from the non-body-contacting side. However, access is more restricted when implemented as a conventional style of one-piece appliance, as illustrated by the pouch 20 in FIG. 1 of the accompanying drawings. The wearer can only access the moldable adhesive 21 to mold the stomal aperture from a body-contacting side 22, and not from an opposite non-body-contacting side 23 that is covered by the immovable pouch 20. This makes molding the adhesive more difficult, and means that the shape and size of the aperture might not be as accurate as would be when the adhesive is accessible from both sides.
WO2004/084777 and WO2006/035014 describe alternative one-piece ostomy pouches in which an adhesive wafer is attached to the pouch using two different types of attachment extending in complementary first and second angular sectors or arcs that together extend completely around the stoma aperture. In the first angular sector around the stoma aperture, the wafer is permanently attached immovably. In the second angular sector around the aperture, the wafer is initially unattached or is releasably attachable. The second angular sector is said to permit the pouch to be partly folded ajar of the wafer in the limited region of the second sector, allowing access through the gap created between the wafer and the pouch. This access is said to facilitate cutting the adhesive, or fitting a separate sealing member, or removal and fitting of a separate disposable inner pouch. However, such a solution illustrates the inherent incompatibilities associated with trying to combine two-piece behavior with an immovable body fitment of a one-piece appliance. With such a solution, the first sector in which the body fitment is immovable, hinders access to the body fitment because the pouch cannot be folded away in this region. Unless the second sector is made exceptionally large, access to the adhesive as a whole may still be restricted, making it difficult for an elderly or non-dexterous person to use the appliance. Additionally, there may be vulnerabilities in the seal between the faceplate and the pouch at (i) the points at where the first and second sectors meet around the periphery of the stoma aperture, and/or (ii) at the folding notches or creases of the stiffening ring that is used, in view of the discontinuities which are inevitable at all of these points.
A further manufacturing limitation of the conventional one-piece style of FIG. 1, and the alternative arrangements described in WO2004/084777 and WO2006/035014, is that the pouch 20 typically needs to be dimensioned to extend beyond the extremity of the adhesive 21 on all sides. This geometry is believed present in all of the mass-produced one-piece pouches currently available, and is a consequence of the manufacturing techniques used. The techniques typically require space for manufacturing equipment to come into intimate contact with the material for the pouch walls 24, 25 to form a peripheral weld 26 and stamp the material, after the adhesive 21 has already been attached in its operative position around the entrance aperture 27. The pouch 20 usually extends significantly below the entrance aperture 27 to provide the main collection volume of the pouch 20, and so this geometry poses no problems for the lower portion of the pouch. However, the need for the pouch 20 also to extend upwardly above, and/or to either side of, the adhesive 22 results in unused headspace 28. Such headspace 28 is undesirable because it cannot easily be used as part of the collection volume of the pouch, and it merely adds undesirably to the size of the pouch 20.
The present invention provides surprising solutions to these problems